Innovative low-energy evaporative cooling system for buildings: study of the porous evaporator wall

• Published in: Journal of building performance simulation 2019-03, Vol.12 (2), p.208-223
• Main Authors: Leroux, Guilian, Mendes, Nathan, Stephan, Louis, Le Pierrès, Nolwenn, Wurtz, Etienne
• Format: Article
• Language: English
• Subjects: Cooling; Cooling systems; Engineering Sciences; Evaporative cooling; evaporative cooling system; Evaporators; heat and moisture transfer; intrinsic permeability; low-energy buildings; Material properties; Mathematical models; Parametric analysis; Porous materials; porous materials for cooling systems
• ISSN: 1940-1493; 1940-1507
• DOI: 10.1080/19401493.2018.1501094

To face the current increase of building cooling demand and the concerns related to climate changes, an energy-efficient evaporative cooling system using porous material has been developed. This article presents the innovative cooling system and a detailed hygrothermal analysis of its main element: the porous evaporator. A mathematical model and an experimental set-up are presented, which enable to determine the suitable material properties for the evaporator and its impact on the overall cooling system performance, focusing on the optimal use of both energy and water. A good agreement is observed between numerical and experimental results, and the evaporative cooling power is estimated from 12 to 72 W/m² of evaporator wall, depending on the evaporator characteristics. A parametric analysis is conducted to select the best material for the evaporative cooling system. An intrinsic permeability of the material of 4 × 10 −17  m 2 is recommended for this new cooling system.